Automatic adjustment of thermal requirement

ABSTRACT

Methods and apparatuses to automatically adjust a thermal requirement of a data processing system are described. One or more conditions associated with a data processing system are detected. A temperature requirement for the data processing system is determined based on the one or more conditions. The performance of the data processing system may be throttled to maintain a temperature of the data processing system below the temperature requirement. Detecting the one or more conditions associated with the data processing system may include determining a location of the data processing system based on a measured motion, a state of a peripheral device, a position of one portion of the data processing system (e.g., a lid) relative another portion of the data processing system (e.g., a bottom portion), a type of application operating on the data processing system, or any combination thereof.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional of co-pending U.S. patent applicationSer. No. 12/564,025, filed on Sep. 21, 2009, which claims benefit toprior U.S. Provisional Patent Application No. 61/160,268, entitled“AUTOMATIC ADJUSTMENT OF THERMAL REQUIREMENT” filed on Mar. 13, 2009,which is hereby incorporated by reference.

FIELD OF THE INVENTION

At least some embodiments of the present invention relate generally todata processing systems, and more particularly but not exclusively tothe management of power and/or thermal characteristics in dataprocessing systems.

BACKGROUND

Traditionally, computer systems are designed to be able to continuouslyrun a fairly worst-case power load. Design according to such acontinuous worst-case power load has never been much of a problem,because traditionally the individual components have had modestoperating powers and the computer systems have had large power budgetsso that the systems could sustain the load fairly naturally.

As the operating power consumptions of the individual components ofcomputer system creep upwards, the power budgets of the computer systemshave become tighter. It is now becoming a challenge to design a computersystem to keep its temperature below a critical temperature whilepursuing various goals, such as high computing power, compactness,quietness, better battery performance, etc. The critical temperature canbe defined as a temperature at or near a surface of the computer system,such as a bottom of a laptop computer or the bottom of a cellulartelephone (e.g., a “smartphone”).

Typically, for computer systems the value of a critical temperaturethreshold involves an important temperature-performance trade-off.Generally, a low critical temperature threshold provides the user with abetter cooling experience, whereas a high critical temperature thresholdprovides better performance. Currently, a critical temperature thresholdof the computer system cannot be adjusted. Typically, a criticaltemperature threshold is set at a computer manufacturing stage in themiddle between the high critical temperature threshold and the lowcritical temperature threshold as a compromise between the coolingexperience and the performance.

SUMMARY OF THE DESCRIPTION

Methods and apparatuses to automatically adjust a thermal requirement ofa data processing system are described. One or more conditionsassociated with a data processing system are detected. A temperaturerequirement for the data processing system can be determined based onthe one or more conditions. The performance of the data processingsystem can be throttled to maintain a temperature of the data processingsystem below the temperature requirement.

In at least some embodiments, detecting the one or more conditionsassociated with the data processing system may include determining alocation of the data processing system based on a measured motion, astate of a peripheral device, determining a position of one portion ofthe data processing system (e.g., a lid) relative another portion of thedata processing system (e.g., a bottom portion), a type of applicationoperating on the data processing system, or any combination thereof. Thethermal requirements for each of the one or more conditions may bepredicted, and the predicted thermal requirements for each of the one ormore conditions may be weighed to determine the temperature requirementof the data processing system.

In at least some embodiments, the temperature requirement of the dataprocessing system includes selecting a temperature set point based onthe detected one or more conditions of the data processing system.

In at least some embodiments, the data processing system thatautomatically adjusts the thermal requirement includes a portabledevice.

In at least some embodiments, a motion of a data processing system isdetected. A position of the data processing system may be determinedbased on the detected motion. A temperature set point for the dataprocessing system may be adjusted based on the position of the dataprocessing system. In at least some embodiments, adjusting thetemperature set point includes selecting the temperature set point basedon the detected position of the data processing system. The performanceof the data processing system may be throttled to maintain the dataprocessing system temperature below the adjusted temperaturerequirement.

In at least some embodiments, detecting the motion associated with adata processing system includes measuring accelerations associated withthe data processing system. The acceleration can be measured, in oneembodiment, with an accelerometer, which is used to protect a hard diskdrive from sudden accelerations.

In at least some embodiments, determining the position of the dataprocessing system includes increasing a confidence for a first locationof the data processing system if the motion is not detected within afirst time interval; and increasing the confidence for a second locationof the data processing system if the motion is detected within the firsttime interval.

In at least some embodiments, determining the position of the dataprocessing system includes increasing a confidence for a first locationif a rate of the motion is less than a rate threshold; and increasingthe confidence for a second location of the data processing system if arate of the motion is more than a rate threshold.

In at least some embodiments, determining the position of the dataprocessing system includes increasing a confidence for a first locationif a range of the motion is less than a range threshold; and increasingthe confidence for a second location of the data processing system if arange of the motion is more than a range threshold.

Other features of the present invention will be apparent from theaccompanying drawings and from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 illustrates one embodiment of a system to automatically adjust athermal requirement.

FIG. 2 illustrates another embodiment of a system to dynamically adjustthermal requirement based on one or more conditions.

FIG. 3 shows one embodiment of a graph illustrating a rough performancegain versus a critical temperature threshold for a data processingsystem.

FIG. 4A shows one embodiment a block diagram to predict a thermalrequirement for a data processing system based on one or moreconditions.

FIG. 4B shows one embodiment of a look-up table to select thermalrequirements for various conditions.

FIG. 4C shows one embodiment of a look-up table to select a performancesetting for the data processing system according to various thermalrequirements.

FIG. 5 is a block diagram illustrating an exemplary architecture of aportable data processing system according to one embodiment of theinvention.

FIG. 6A illustrates one embodiment of signatures of motions at differentlocations of a data processing system.

FIG. 6B illustrates one embodiment of determining a range ofdisturbances.

FIG. 7 shows one embodiment of a cumulative distribution function(“CDF”) of interarrival time of disturbances when a data processingsystem is located at different locations.

FIG. 8 shows a diagram of one embodiment of a predicting a locationusing a confidence counter.

FIG. 9 shows a table to determine a location of a data processing systemaccording to one embodiment.

FIG. 10 shows a graph illustrating one embodiment of a dependence of atemperature 1002 of a data processing from time 1001 when the dataprocessing system is moved from one location (e.g., a desk) to anotherlocation (e.g., a lap).

FIG. 11 is a flowchart of one embodiment of a method to automaticallypredict a thermal requirement of a data processing system.

FIG. 12 is a flowchart of one embodiment of a method to adjust a thermalrequirement of a data processing system based on a location.

FIG. 13 is a flowchart of one embodiment of a method to detect adisturbance associated with a motion.

FIG. 14 is a flowchart of one embodiment of a method 1400 to determine alocation of a data processing system.

FIG. 15 is a flowchart of one embodiment of a method to determine alocation of a data processing system based on a motion.

FIG. 16 is a flowchart of a method to determine a location of a dataprocessing system based on a detected motion.

DETAILED DESCRIPTION

Various embodiments and aspects of the inventions will be described withreference to details discussed below, and the accompanying drawings willillustrate the various embodiments. The following description anddrawings are illustrative of the invention and are not to be construedas limiting the invention. Numerous specific details are described toprovide a thorough understanding of various embodiments of the presentinvention. It will be apparent, however, to one skilled in the art, thatembodiments of the present invention may be practiced without thesespecific details. In other instances, well-known structures and devicesare shown in block diagram form, rather than in detail, in order toavoid obscuring embodiments of the present invention.

Reference in the specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the invention. The appearances of the phrase “in one embodiment” invarious places in the specification do not necessarily refer to the sameembodiment.

Unless specifically stated otherwise, it is appreciated that throughoutthe description, discussions utilizing terms such as “processing” or“computing” or “calculating” or “determining” or “displaying” or thelike, refer to the action and processes of a data processing system, orsimilar electronic computing device, that manipulates and transformsdata represented as physical (electronic) quantities within the computersystem's registers and memories into other data similarly represented asphysical quantities within the computer system memories or registers orother such information storage, transmission or display devices.

Embodiments of the present invention can relate to an apparatus forperforming one or more of the operations described herein. Thisapparatus may be specially constructed for the required purposes, or itmay comprise a general purpose computer selectively activated orreconfigured by a computer program stored in the computer. Such acomputer program may be stored in a machine (e.g., computer) readablestorage medium, such as, but is not limited to, any type of disk,including floppy disks, optical disks, CD-ROMs, and magnetic-opticaldisks, read-only memories (ROMs), random access memories (RAMs),erasable programmable ROMs (EPROMs), electrically erasable programmableROMs (EEPROMs), magnetic or optical cards, or any type of media suitablefor storing electronic instructions, and each coupled to a bus.

A machine readable medium can be used to store software and data whichwhen executed by a data processing system causes the system to performvarious methods of the present invention. This executable software anddata may be stored in various places including for example ROM, volatileRAM, non-volatile memory, and/or cache. Portions of this software and/ordata may be stored in any one of these storage devices.

Thus, a machine readable medium includes any mechanism that provides(i.e., stores and/or transmits) information in a form accessible by amachine (e.g., a computer, network device, cellular phone, personaldigital assistant, manufacturing tool, any device with a set of one ormore processors, etc.). For example, a machine readable medium includesrecordable/non-recordable media (e.g., read only memory (ROM); randomaccess memory (RAM); magnetic disk storage media; optical storage media;flash memory devices; and the like.

The algorithms and displays presented herein are not inherently relatedto any particular computer or other apparatus. Various general-purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct more specializedapparatus to perform the required machine-implemented method operations.The required structure for a variety of these systems will appear fromthe description below.

In addition, embodiments of the present invention are not described withreference to any particular programming language. It will be appreciatedthat a variety of programming languages may be used to implement theteachings of embodiments of the invention as described herein.

Many of the methods of the present invention may be performed with adigital processing system, such as a conventional, general-purposecomputer system. The computer systems may be, for example, entry-levelMac Mini™ and consumer-level iMac™ desktop models, the workstation-levelMac Pro™ tower, and the MacBook™, MacBook Pro™ laptop computers producedby Apple Inc., located in Cupertino, Calif. Small systems (e.g. verythin laptop computers, like MacBook Air™) can benefit from the methodsdescribed herein. Special purpose computers, which are designed orprogrammed to perform only one function, or consumer electronic devices,such as a cellular telephone, may also perform the methods describedherein.

Methods and apparatuses to automatically adjust a thermal requirement ofa data processing system are described herein. One or more conditionsassociated with a data processing system are detected at a current time.A temperature requirement for the data processing system can bepredicted for a future time based on the detected one or moreconditions. The thermal requirement (e.g., a temperature set point or atarget temperature) of the data processing system can be adjusted to thepredicted temperature requirement based on the detected one or moreconditions. The one or more conditions associated with the dataprocessing system may be, for example, a state of the data processingsystem, a location of the data processing system, a type of applicationand/or quantity of applications operating on the data processing system,as described in further detail below. For example, a temperature setpoint for the laptop computer may be decreased when it is detected thatthe laptop computer is at one location (e.g., on a user's lap), and thetemperature set point may be increased when it is detected that thelaptop computer is at a different location (e.g., on a desk). Further,the performance of the data processing system can be throttled tomaintain a temperature of the data processing system below the adjustedtemperature requirement. For example, the performance of a laptopcomputer may be throttled so that its external temperature remains belowan adjusted critical threshold.

FIG. 1 illustrates one embodiment of a system to automatically adjust athermal requirement. As shown in FIG. 1 system 100 includes a subsystem101, e.g., a Central Processing Unit (“CPU”), a subsystem 102, e.g., aGraphics Processing Unit (“GPU”) that may be coupled with a displaydevice, and one or more subsystems 109, e.g., one or more Input/Output(“I/O”) controllers coupled to one or more I/O devices, and amicrocontroller 107 coupled to a bus 110. The subsystem 101 and/orsubsystem 102 may include, for example, an Intel Pentium microprocessor,or Motorola Power PC microprocessor, such as a G3 or G4 microprocessors,or IBM microprocessor. The data processing system 100 may interface toexternal systems through a modem or network interface (not shown). Itwill be appreciated that the modem or network interface (not shown) canbe considered to be part of the data processing system 100. Thisinterface can be an analog modem, ISDN modem, cable modem, token ringinterface, satellite transmission interface, or other interfaces forcoupling a data processing system to other data processing systems.

Further, system 100 includes a volatile RAM 104, a non-volatile storage106, e.g., a hard drive, Read-only memory (“ROM”) 103, and a cachememory 105 coupled to subsystem 101 which is coupled to bus 110. Memory104 can be dynamic random access memory (DRAM) and can also includestatic RAM (SRAM). Memory 104 may include one or more memory buffers.The non-volatile storage 106 is often a magnetic hard disk, an opticaldisk, or another form of storage for large amounts of data. Some of thisdata is often written, by a direct memory access process, into memory104 during execution of software in the data processing system 100. Oneof skill in the art will immediately recognize that the terms“computer-readable medium” and “machine-readable medium” include anytype of storage device that is accessible by the processor, such as aprocessor unit of subsystem 101.

The bus 110 couples the subsystem 101 to the memories 104 and 103 andalso to non-volatile storage 106 and to subsystem 102 and to subsystem109. The subsystem 102 may include a display controller (not shown) thatcontrols in the conventional manner a display on a display device (notshown) which can be a cathode ray tube (CRT) or liquid crystal display(LCD). The subsystem 109 may include an I/O controller (not shown)coupled to one or more input/output devices (e.g., a keyboard, diskdrives, printers, a scanner, speakers, microphone, camera, and otherinput and output devices, including a mouse or other pointing device).In one embodiment, the I/O controller of subsystem 109 includes a USB(Universal Serial Bus) adapter for controlling USB peripherals, and/oran IEEE-1394 bus adapter for controlling IEEE-1394 peripherals.

As shown in FIG. 1, one or more measuring devices 108 are coupled tosubsystems 101, 102, 109, and to microcontroller 107, as shown inFIG. 1. The measuring devices 108 may be used to detect one or moreconditions of the data processing system 100, as described in furtherdetail below. In one embodiment, one or more tables containing thermalrequirements and corresponding performance settings, as set forth infurther detail below, are stored in any of memories 103, 104, andstorage 106 or within a memory in a microcontroller 107. In oneembodiment, microcontroller 107 performs methods to automatically adjusta thermal requirement for system 100 based on one or more conditions, asdescribed in further detail below. In another embodiment, subsystem 101,rather than microcontroller 107, performs methods to automaticallyadjust a thermal requirement for system 100 based on one or moreconditions, as described in further detail below.

It will be appreciated that the data processing system 100 is oneexample of many possible data processing systems which have differentarchitectures. For example, personal computers based on an Intelmicroprocessor often have multiple buses, one of which can be aninput/output (I/O) bus for the peripherals and one that directlyconnects the subsystem 101 and the memory 104 and/or memory 103 (oftenreferred to as a memory bus). The buses are connected together throughbridge components that perform any necessary translation due todiffering bus protocols.

Network computers are another type of data processing system that can beused with the embodiments of the present invention. Network computers donot usually include a hard disk or other mass storage, and theexecutable programs are loaded from a network connection into the any ofmemories 103, 104, and/or storage 106 for execution by the processor,e.g., a processor of subsystem 101. A Web TV system, which is known inthe art, is also considered to be a data processing system according tothe embodiments of the present invention, but it may lack some of thefeatures shown in FIG. 1, such as certain input or output devices. Atypical data processing system will usually include at least aprocessor, memory, and a bus coupling the memory to the processor.

The methods to automatically adjust a temperature requirement of a dataprocessing system, as set forth in further detail below can beimplemented using dedicated hardware (e.g., using Field ProgrammableGate Arrays, or Application Specific Integrated Circuit) or sharedcircuitry (e.g., microprocessors or microcontrollers under control ofprogram instructions stored in a machine readable medium. The methods ofthe present invention can also be implemented as computer instructionsfor execution on a data processing system, such as system 100 of FIG. 1.

FIG. 2 illustrates another embodiment of a system to dynamically adjustthermal requirement based on one or more conditions. As shown in FIG. 2system 200 includes a subsystem A 201, e.g., a CPU, a subsystem B 202,e.g., a GPU that may be coupled with a display device, subsystem C 204,e.g., a memory, subsystem D 205, e.g., a microprocessor, and one or moresubsystems N 203, e.g., one or more I/O controllers coupled to one ormore I/O devices, a power manager 208, e.g., a microcontroller, a systemmanagement controller (“SMC”), coupled to a interconnect 206, e.g, abus. Subsystem C 204 may be a volatile RAM, a non-volatile memory, e.g.,a hard drive, and/or a ROM. One or more measuring devices 207, e.g., oneor more sensors to detect one or more conditions associated with system200 are coupled to subsystems 201-205, and to power manager 208, asshown in FIG. 2.

A thermal requirement look-up table 209 that may include performancesettings (e.g, voltage, frequency), and conditions for the system 200,is coupled to power manager 208, as shown in FIG. 2. Components of thesystem 200, including processors, microcontrollers, buses, I/Ocontrollers, I/O devices, memories, sensors are described above withrespect to FIG. 1. In one embodiment, one or more thermal requirementlookup tables corresponding to various performance settings andconditions of the computer system may be generated by subsystem 201 (orgenerated by test equipment in the design and/or manufacturing process),and stored in memory 204, and/or in a memory located in power manager208. In one embodiment, power manager 208 performs methods todynamically adjust thermal requirement for the system. In anotherembodiment, subsystem 201 performs methods to dynamically adjust thermalrequirement for the system.

FIG. 3 shows one embodiment of a graph 300 illustrating a roughperformance gain 301 versus a critical temperature threshold 302 for adata processing system. As shown in FIG. 3, a performance gain 303increases when a critical temperature threshold 302 increases. As shownin FIG. 3, the value of the critical threshold for a data processingsystem needs to be chosen carefully as it can significantly affect theperformance of the data processing system. That is, a significanttemperature-performance tradeoff is involved.

For example, as shown in FIG. 3, a critical temperature threshold of 45C may provide the lower temperature (better cooling experience and usersatisfaction) while providing a lower performance, and the criticaltemperature threshold of 50 C may provide the higher performance whileproviding the higher temperature (worse cooling experience and worseuser satisfaction). Generally, a compromise is made and a fixedtemperature threshold in the middle, like 47 C, may be chosen. In a realworld, however, a user may want a cooler machine (45 C), for example,when the data processing system (e.g., a laptop computer) is at onelocation (e.g., on a user's lap).

A user may want a better performance (49 C-50 C) of a data processingsystem (e.g., a laptop computer), for example, when the system is atanother location (e.g., on a desk). As shown in FIG. 3, for every degreeof restriction on an external temperature of the system (criticaltemperature threshold), there may be a significant impact on theperformance. A desired thermal requirement for a data processing systemmay be entered by a user through a user interface (not shown). The userinterface may include, for example, a ‘temperature requirementscrollbar’ or a check box allowing a user to set a thermal requirement.The check box may, for example, have options “set a first thermalrequirement if the laptop will not be at a first location”, “set asecond thermal requirement if the laptop will be at the first location”and/or “set a third thermal requirement if the lid of the laptop is notclosed”, and the like. The thermal requirement of the data processingsystem may be adjusted based on the entered thermal requirement. In oneembodiment, a thermal requirement for a data processing system ispredicted and dynamically adjusted based on a user's behavior or actionto provide an optimal performance-user satisfaction trade-off, as setforth in further detail below.

FIG. 4A shows one embodiment a block diagram to predict a thermalrequirement for a data processing system based on one or moreconditions. As shown in FIG. 4A, a condition associated with a dataprocessing system may be a physical condition of the data processingsystem 401, a location of the data processing system 402, a type ofapplication operating on the data processing system, and/or a quantityof applications operating on the data processing system (not shown).

In one embodiment, detecting physical condition 401 involves determininga position of one portion of a data processing system (e.g., a lid)relative another portion of the data processing system (e.g., a bottomportion). In another embodiment, detecting physical condition 401involves determining a state of a peripheral device, e.g., determiningwhether a peripheral device, such as a keyboard, display, mouse, etc.,is connected to the data processing system. In one embodiment, a thermalrequirement for the data processing system for a subsequent time ispredicted based on the detected physical condition 401. For example, ahigher thermal requirement (e.g., a higher critical external temperatureset point) can be predicted if the laptop's lid is closed, and/or aperipheral device is connected, and a lower thermal requirement (e.g., alower critical external temperature set point) is predicted if thelaptop's lid is opened, and/or a peripheral device is not connected.

In one embodiment, detecting location 402 may include measuring a motionassociated with the data processing system; and determining a location(e.g., on a user's lap or a desk) of the data processing system based onthe motion. In one embodiment, a thermal requirement for the dataprocessing system for a subsequent time is predicted based on thedetected physical location of the data processing system 402. In oneembodiment, it is determined whether a laptop is on a user's lap or on adesk. In one embodiment, a lower thermal requirement (e.g., a lowercritical external temperature set point) is predicted if the laptop ison a user's lap, and higher thermal requirement (e.g., a higher criticalexternal temperature set point) is predicted if the laptop is on a desk.

Detecting a type of application 403 may involve, for example, detectingwhether an application requiring a lot of power (e.g, a 1080p HighDefinition movie) is running on the data processing system. In oneembodiment, a thermal requirement for the data processing system for asubsequent time is predicted based on the detected type of applicationrunning on the data processing system 403. In one embodiment, a higherthermal requirement (e.g., a higher critical external temperature setpoint) is predicted if the high definition movie application isoperating on the data processing system, and a lower thermal requirement(e.g., a lower critical external temperature set point) is predicted ifa word processor application is operating on the data processing system.In one embodiment, the predictions determined based on each of thedetected conditions are weighed. As shown in FIG. 4A, an output 405including a thermal requirement for the data processing system ispredicted based on a combination of the weighted predictions 404.

FIG. 11 is a flowchart of one embodiment of a method to automaticallypredict a thermal requirement of a data processing system. Method 1100begins with operation 1101 that involves detecting one or moreconditions associated with a data processing system at a current time.Method 1100 continues with an optional operation 1102 involvingpredicting thermal requirements for the data processing system based oneach of the one or more conditions. In one embodiment, predicting thetemperature requirement includes selecting a critical externaltemperature set point (critical temperature threshold) for the dataprocessing system corresponding to the detected one or more conditionsfrom a look up table stored in a memory.

FIG. 4B shows one embodiment of a look-up table to select thermalrequirements for various conditions. Typically, the critical temperaturetargets for safety and customer satisfaction can be estimated during aproduct development stage. Usually, customer satisfaction temperaturetargets for the data processing system are significantly lower than thesafety temperature targets for the data processing system.

As shown in FIG. 4B, look-up table 410 includes thermal requirements(e.g., critical external temperature set points T1-TN) corresponding todifferent conditions 412 C1-CN (e.g., conditions 401-403). Look-up table410 can be stored in a memory of the data processing system. Thermalrequirements T1-TN can be selected from table 410 for each of thedetected conditions 412.

Referring back to FIG. 11, at operation 1103 the predicted thermalrequirements for each of the one or more conditions are weighted. In oneembodiment, more weight is given to the physical condition 401 than tothe location 402 and type of application 403. In another embodiment,more weight is given to the physical condition 401 and to the type ofapplication 403 than to the location 402. In yet another embodiment,more weight is given to the location 402 than to the physical condition401 and type of application 403. At operation 1103 the weightedpredicted thermal requirements for each of the one or more conditionsare combined to output a predicted combined thermal requirement for thedata processing system.

Method continues with operation 1104 that involves throttling aperformance of the data processing system based on the predictedcombined thermal requirement to maintain an external data processingsystem temperature below the combined temperature requirement. In oneembodiment, throttling the performance involves adjusting operatingvoltage and/or frequency of the data processing system based on thepredicted combined thermal requirement. In one embodiment, an operatingvoltage and/or frequency of the data processing system is adjusted byselecting an operating voltage and/or operating frequency from a look uptable stored in a memory according to the predicted combined thermalrequirement.

FIG. 4C shows one embodiment of a look-up table to select a performancesetting (e.g., operating voltage and/or frequency) for the dataprocessing system according to various thermal requirements. Look-uptable 420 includes performance settings 422 and 413 (e.g., voltagesV1-VN and frequencies f1-fN) for the data processing system thatcorrespond to the thermal requirements 421 (e.g., combined thermalrequirements T1 c-TNc).

FIG. 12 is a flowchart of one embodiment of a method to adjust a thermalrequirement of a data processing system based on a location. Method 1200begins with operation 1201 involving detecting a motion of a dataprocessing system, as set forth in further detail below. In oneembodiment, detecting the motion of the data processing system includesmeasuring accelerations associated with the data processing system. Atoperation 1202 a position of the data processing system is determinedbased on the detected motion, as set forth in further detail below. Atemperature set point (e.g., external critical temperature set point)for the data processing system is adjusted based on the determinedposition at operation 1203, as set forth in further detail below. Aperformance of the data processing system is throttled to maintain adata processing system temperature below the adjusted temperature setpoint at operation 1209.

FIG. 5 is a block diagram illustrating an exemplary architecture of aportable data processing system (e.g., a laptop computer) according toone embodiment of the invention. In one embodiment, the exemplary system500 includes, but is not limited to, a processor, a memory coupled tothe processor, the memory having instructions stored therein, and anaccelerometer coupled to the processor and the memory to detect movementof the portable device, where the processor executes instructions fromthe memory to perform one or more predetermined user configurableactions in response to the detection of the movement of the portabledevice. In an alternative embodiment, the exemplary system 500 furtherincludes a controller coupled to the accelerometer to determine adirection of the movement based on movement data provided by theaccelerometer and to compare the determined direction of the movementwith a predetermined direction to determine whether the determineddirection relatively matches the predetermined direction in order toexecute the instructions.

Referring to FIG. 5, according to one embodiment, exemplary system 500includes one or more accelerometers 501, one or more controllers 502coupled to the accelerometers 501, a motion related firmware 503, motionsoftware component 504, and one or more application software 505-507.The accelerometer 501 may be attached to the portable device, such as,for example, a motherboard of the portable device. Alternatively, theaccelerometer 501 may be integrated with another component of theportable device. For example, the accelerometer 501 may be integratedwith a chip set of the portable device.

According to one embodiment, the accelerometer 501 is able to detect amovement including an acceleration and/or de-acceleration of theportable device. In one embodiment, the accelerometer 501 is alwaysturned on to measure a motion of the data processing system even whenthe memory disk is not spinning. The accelerometer 501 may generatemovement data for multiple dimensions, which may be used to determine amoving direction of the portable device. For example, the accelerometer501 may generate X, Y, and Z axis acceleration information when theaccelerometer 501 detects that the portable device is moved. In oneembodiment, the accelerometer 501 may be implemented as those describedin U.S. Pat. No. 6,520,013, which is assigned to a common assignee ofthe present application. Alternatively, the accelerometer 501 may beimplemented using a variety of accelerometers commercially available.For example, the accelerometer 501 may be a KGF01 accelerometer fromKionix or an ADXL311 accelerometer from Analog Devices.

In addition, the exemplary system 500 includes one or more controllers502 coupled to the accelerometer(s) 501. The controller 502 may be usedto calculate a moving direction, also referred to as moving vector, ofthe portable device. The moving vector may be determined according toone or more predetermined formulas based on the movement data (e.g., X,Y, and Z axis moving information) provided by the accelerometer 501, asdescribed in details in U.S. patent application Ser. No. 10/986,730filed Nov. 12, 2004, which is incorporated by reference herein in itsentirety.

According to one embodiment, the controller 502 is responsible formonitoring one or more outputs of the accelerometer 501 andcommunicating with other components, such as, for example, a chipset(e.g., a memory controller or a north bridge) and/or a microprocessor(e.g., a CPU), of the portable device. The controller 502 may beimplemented using a variety of microcontrollers commercially available.For example, controller 502 may be a PIC 16F818 microcontroller fromMicrochip. Controller 502 may be integrated with the accelerometer 501.Alternatively, controller 502 may be integrated with other components,such as, for example, a chipset or a microprocessor, of the portabledevice.

In one embodiment, the controller 502 may communicate with othercomponents via a bus, such as, for example, an I2C (inter-IC) bus, andan interrupt line. In response to the movement data, the controller 502generates an interrupt, for example, a hardware interrupt, a softwareinterrupt, or a combination of both, via an interrupt line to othercomponents, such as, firmware 503, to notify them of such a movement. Inaddition, the controller 502 may further calculate a moving vector basedon the movement data provided by the accelerometer 501, as described inU.S. patent application Ser. No. 10/986,730.

Referring back to FIG. 5, motion firmware 503 includes one or morepieces of machine executable code, which may be embedded within one ormore hardware components, such as, for example, controller 502 or achipset (e.g., a part of BIOS, also referred to as basic input/outputsystem), of the portable device. In one embodiment, motion firmware 503may be stored in a read-only memory (ROM) (e.g., a flash memory) ofcontroller 502. However, the machine executable code of motion firmware503 may be upgraded by uploading a newer version into the memory, forexample, using a flash utility. The firmware 503 may be responsible fordetecting any events that are generated in response to the movementdetection. According to one embodiment, the firmware 503 provides aprimary communications mechanism between controller 502 and othercomponents, such as, for example, an operating system (OS), of theportable device.

Motion software 504 may be responsible for communicating between themotion firmware 503 and the rest of software components, such asapplication software components 505-507, as well as the operatingsystem. In one embodiment, the motion software 504 may be implemented asa part of an operating system, such as, for example, a kernel componentor a device driver, etc. The operating system may be implemented using avariety of operating systems commercially available. For example, theoperating system may be a Mac OS from Apple Computer. Alternatively, theoperating system may be a Windows operating system from Microsoft. Otheroperating systems, such as, for example, a Unix, a Linux, an embeddedoperating system (e.g., a Palm OS), or a real-time operating system, mayalso be implemented.

According to one embodiment, in response to the motion detection event,which may be notified by the motion firmware 503, the motion softwarecomponent 504 may communicate the event to one or more applicationsoftware 505-507. The applications 505-507 may be a variety of differentapplications, such as, for example, an application to automaticallyadjust a thermal requirement of a data processing system based on thedetected motion, a browser, a word processor, a slide presentation, etc.In one embodiment, an accelerometer is used for protecting a disk drivefrom sudden accelerations and for automatic adjustment of a thermalrequirement of a data processing system.

FIG. 6A illustrates one embodiment of signatures of motions at differentlocations of a data processing system. These motions can be captured bya motion sensor, e.g., an accelerometer, as described above. As shown inFIG. 6A, a graph 606 of a range of motion 602 versus interarrival time601 showing a signature of the motion generated when a data processingsystem is at one location (e.g., a laptop on a user's lap) issignificantly different from a graph 606 of a range of motion 602 versusinterarrival time 601 showing a signature of the motion 607 that isgenerated when a data processing system is at another location (e.g.,when a desk, or the laptop upon it, is hit). Signature of motion 604 hassmall but frequent disturbances 604, whereas signature of motion 607 hasa single large disturbance 605. That is, disturbances 604 have smallerrange of motion 602 than disturbance 605. As shown in FIG. 6A, at leastone disturbance 604 occurs during a time 603 (e.g., a human stabilityperiod).

The small and frequent disturbances 604 are caused typically by anunstable support when a laptop is on a user's lap and an involuntarymotion of user's muscles. The unstable support typically generates smalldisturbances, e.g., when the user interacts with a computer through aninput device, e.g., a keyboard, touchpad, etc. The frequency of thesedisturbances depends on the type of work that the user is currentlydoing. For example, the frequency will be higher when the user is typinga document and will be lower when the user is watching a movie.

The involuntary motion of muscles can occur because users typicallycannot stay in the same posture for a long period of time. Typically,users constantly move their body, for example by moving legs, changingsitting posture, swiveling on a chair, moving the laptop from oneportion of the lap to another, etc. The involuntary motion of user'smuscles small disturbances that are captured by motion sensor. Thefrequency of these disturbances may vary from one user to another andmay depend on a level of satisfaction that the user has with the currentposture.

That is, when the laptop is on a user's lap, it is highly probable thatat least one small disturbance within a certain time (e.g., a humanstability period T_(hs)) is detected. In one embodiment, the value ofT_(hs) is determined empirically, such that a probability that adisturbance is generated within time T_(hs), when the laptop is on auser's lap is very high (e.g., more than 90%):

P(a disturbance is generated within time T _(hs)/laptop is on a user'slap) is high  (1)

and

a probability that a disturbance is generated within time T_(hs) whenthe laptop is on the desk is very low (e.g., less than 90%):

P(a disturbance is generated within time T _(hs)/laptop is on a desk) islow  (2).

A human stability period (T_(hs)) can be visualized by modeling thearrival process of the disturbances using a Poisson random variable.When the laptop is on a user's lap, the arrival rate of the disturbances(λ_(lap)) is significantly greater than the arrival rate when the laptopis on a desk (λ_(desk)), such that λ_(lap)>λ_(desk). The inter-arrivaltime thus follows exponential distribution with a mean 1/λ_(lap) in caseof a user's lap, and mean 1/λ_(desk) in case of a desk.

FIG. 7 shows one embodiment of a cumulative distribution function(“CDF”) of interarrival time of disturbances when a data processingsystem (e.g., a laptop) is located at different locations. As shown inFIG. 7, the CDF 702 versus interarrival time 701 (e.g., time between thedisturbances, entropy interval time) dependence for one location of adata processing system 703 is different from the CDF of disturbancesversus time dependence for another location of the data processingsystem 704. The arrival process of disturbances follows Poissondistribution such that the arrival rate of disturbances when the dataprocessing system is at one location 703 (e.g., λlap) is greater thanthe arrival rate of disturbances when the data processing system is atanother location 704 (e.g., λdesk). A conceptual location of a humanstability period T hs 705 on the CDF plots of inter-arrival time ofdisturbances is shown in FIG. 7.

Using Bayesian Inference on (1) & (2) set forth above, the likelihoodthat the laptop is on a user's lap, given that no disturbance isdetected within time Ths, is low:

L(laptop is on a user's lap/no disturbance is detected within time Ths)is low  (3).

The above Bayesian inference forms the basis of the predicting thethermal requirement for the data processing system based on a location.

FIG. 13 is a flowchart of one embodiment of a method to detect adisturbance associated with a motion. Method 1300 begins with operation1301 that involves measuring values of accelerations along axes X, Y, Z(e.g, in Cartesian coordinates) at regular time intervals. At operation1302 a range of the accelerations is calculated for every time interval(e.g., entropy time interval TEI). At operation 1303 it is determinedwhether a range of accelerations is greater than a predeterminedthreshold. In one embodiment, the threshold is determined empirically.If the range of accelerations is greater than the predeterminedthreshold, a disturbance associated with a motion is detected atoperation 1304. If the range of accelerations is not greater than thepredetermined threshold, no disturbance is detected at operation 1305.

FIG. 6B illustrates one embodiment of determining a range ofdisturbances. As shown in FIG. 6B, X and Y acceleration values, such asan acceleration value 613, are measured. A range of X accelerationvalues 614 and a range of Y acceleration values 615 are determined. Inone embodiment, calculating the range of accelerations instead of a meanvalue of accelerations provides more accurate determination of alocation of a data processing system having slanting surfaces. Inanother embodiment, a mean value of accelerations is calculated todetermine a location of a data processing system.

FIG. 14 is a flowchart of one embodiment of a method 1400 to determine alocation of a data processing system. As soon as a disturbanceassociated with a motion of a data processing system is detected, adisturbance is checked for a next time interval (e.g., Ths) at operation1401. Method 1400 continues with operation 1402 that includesdetermining whether any further disturbance is detected during the nexttime interval. If the disturbance is detected during the next timeinterval, the likelihood that the data processing system is at a firstlocation (e.g., on a desk) is low (e.g. less than a predeterminedvalue), and the confidence that the data processing system is at asecond location (e.g., on a user's lap) is increased at operation 1403.If no further disturbances is detected during the next time interval, alikelihood of the data processing system being at the second location(e.g., on a user's lap) is low (e.g., less than a predetermined value),and confidence that the data processing system is at a first location(e.g., a desk) is increased at operation 1404.

FIG. 15 is a flowchart of one embodiment of a method to determine alocation of a data processing system based on a motion. Method 1500begins with operation 1502 involving checking for disturbances within atime interval (e.g., Ths). At operation 1502 it is determined whether arate of disturbances is less than a rate threshold. In one embodiment,the rate threshold is determined based on empirical data. If the rate ofthe disturbances is less than the rate threshold, the confidence thatthe data processing system is at a first location (e.g., a desk) isincreased and the confidence that the data processing system is at asecond location is decreased at operation 1503. If the rate ofdisturbances is more than the rate threshold, the confidence that thedata processing system is at a second location (e.g., a user's lap) isincreased and the confidence that a data processing system is at a firstlocation is decreased at operation 1504.

One embodiment of an algorithm to determine a location (e.g., a desk ora lap) for a data processing system based on a disturbance is asfollows:

1. For every T_(Entropyinterval) of time, check if there is adisturbance

2. If there is a disturbance during T_(Entropyinterval) of time.

-   -   a. Check for a disturbance for a next time T_(hs). This can be        realized by resetting the stabilizing counter    -   b. Decrease a desk confidence counter

3. If there is no disturbance

-   -   a. If the stabilizing counter <T_(hs), then prediction of being        on lap remains. Increment the stabilizing counter, but do not        increase the desk confidence counter    -   b. if the stabilizing counter >T_(hs), then increase the desk        confidence counter by one.

If the desk confidence counter is greater than a certain threshold thenthe DeskCase (e.g., a desk location) is predicted, otherwise the LapCase(e.g., a lap location) is predicted. A small amount of hysteresis isincorporated into the algorithm to avoid jumping back and forth betweenLap and Desk.

FIG. 8 shows a diagram of one embodiment of a predicting a locationusing a confidence counter. As shown in FIG. 8, if the desk confidencecounter is greater than 90% the “Desk” is predicted. The “Lap” ispredicted if the desk confidence counter is less than 80%. The currentprediction of a location (e.g., desk or lap) is retained when the deskconfidence counter is between 80% and 90%. The threshold for predictingDesk is generally maintained higher (e.g., 90%) in order to reduce theType-I error (e.g., a False Positive error).

FIG. 9 shows a table 900 to determine a location of a data processingsystem according to one embodiment. Table 900 shows predicted values 903(“Desk” 905 or “Lap” 904) versus True Conditions 901 (“Desk” 902 or“Lap”906). The Null hypothesis is that the laptop is on Lap, and falsepositives need to be minimized, as shown in FIG. 9.

The Type-I error can be further reduced due to the self-correctingbehavior introduced unconsciously by the user. For example, the “Desk”is predicted when the laptop is actually on a lap. This may allow thenotebook to get hotter. If the temperature goes beyond the user'scomfortable point, the user may feel the increase in the temperature andmay start fidgeting. This can generate small disturbances that in turncan decrease the value of desk confidence counter, thereby reducing theprobability of Type-I error.

FIG. 16 is a flowchart of a method to determine a location of a dataprocessing system based on a detected motion. Method 1600 begins withoperation 1601 including checking for a disturbance associated with amotion of a data processing system for every time interval (e.g., anentropy interval of time, the time between the end of the disturbanceand a possible start of a next disturbance). At operation 1602 it isdetermined whether a disturbance is detected. If the disturbance isdetected, a next human stability time period (e.g., Ths) is checked fora disturbance. This can be realized by resetting the stabilizingcounter. For example, if the disturbance is detected, method 1600continues at operation 1603 that involves resetting a stabilizingcounter for a next human stability time period. At operation 1604 afirst location (e.g., a desk) confidence counter is decreased. Atoperation 1605 it is determined whether to check for a next timeinterval (e.g., an entropy interval of time, the time between the end ofthe disturbance and a possible start of a next disturbance) is needed.

If the check for the next time interval is needed, method 1600 continueswith operation 1601 to check for the disturbance for the next timeinterval. If it is determined that the check is not needed, it isdetermined at operation 1606 whether a first location confidence counteris less than a threshold. If the first location confidence counter isless than a second threshold, a second location (e.g., a lap) ispredicted at operation 1608. At operation 1610, if no disturbance isdetected, it is determined whether a stabilizing counter is set to alesser value than a human stability time period (e.g., Ths). If thestabilizing counter is set to a value that is less than the humanstability time period, at operation 1615 the stabilizing counter isincremented without increasing a first location confidence counter.

If the stabilizing counter is set to a value that is not less than thestability time period, the first location (e.g., a desk) confidencecounter is increased at operation 1611. Next, at operation 1612 it isdetermined whether to check for a next time interval. If the check for anext time interval is not needed, at operation 1613 it is determinedwhether the first location confidence counter more than a firstthreshold (TH1). If the first location confidence counter is more than afirst threshold, at operation 1614 a first location (e.g., a desk) ispredicted. If a check for a next time interval is needed, methodcontinues at operation 1601.

If the first location confidence counter is not more than a firstthreshold (TH1), it is determined whether the first location confidencecounter is more than a second threshold and less than a first threshold(TH1<1st CC<TH1). If it is determined that the first location confidencecounter is more than a second threshold and less than a first thresholda current location prediction is retained at operation 1609. If it isdetermined that the first location confidence counter is not more “thana second threshold and less than a first threshold”, method continueswith operation 1606.

FIG. 10 shows a graph illustrating one embodiment of a dependence of atemperature 1002 of a data processing from time 1001 when the dataprocessing system is moved from one location (e.g., a desk) to anotherlocation (e.g., a lap). Curve 1006 illustrates a synthetic (e.g.,modeled) temperature behavior, and curve 1007 illustrates an actual(measured) temperature behavior when the data processing system ismoved. As shown in FIG. 10, the temperature of the data processingsystem (e.g., a laptop) is higher on a desk 103 (49 C-50 C), and loweron a lap 1005 (45 C-46 C). As shown in FIG. 10, the temperature of thelaptop drops 1004 during the transition when the system is moved fromthe desk to the lap. As shown in FIG. 10, the actual temperature 1007drops more rapidly than the synthetic temperature 1006. This may be dueto the contact of the laptop with cold ambient air, which may be around22 C. As a result of adjusting the temperature requirement of the dataprocessing system, as set described herein, the user does not feel thetemperature of the data processing system (e.g., a laptop) greater than45 C.

In the foregoing specification, embodiments of the invention have beendescribed with reference to specific exemplary embodiments thereof. Itwill be evident that various modifications may be made thereto withoutdeparting from the broader spirit and scope of the invention. Thespecification and drawings are, accordingly, to be regarded in anillustrative sense rather than a restrictive sense.

What is claimed is:
 1. A machine-implemented method, comprising:detecting a motion of a data processing system; determining a positionof the data processing system based on the detecting; and adjusting atemperature set point for the data processing system based on theposition.
 2. The machine-implemented method of claim 1, furthercomprising throttling a performance of the data processing system tomaintain a data processing system temperature below the temperature setpoint.
 3. The machine-implemented method of claim 1, wherein thedetecting the motion includes measuring accelerations associated withthe data processing system.
 4. The machine-implemented method of claim1, wherein the determining the position includes increasing a confidencefor a first location of the data processing system if the motion is notdetected within a first time interval; and increasing the confidence fora second location of the data processing system if the motion isdetected within the first time interval.
 5. The machine-implementedmethod of claim 1, wherein the determining the position includesincreasing a confidence for a first location if a rate of the motion isless than a rate threshold; and increasing the confidence for a secondlocation of the data processing system if a rate of the motion is morethan a rate threshold.
 6. The machine-implemented method of claim 1,wherein the determining the position includes increasing a confidencefor a first location if a range of the motion is less than a rangethreshold; and increasing the confidence for a second location of thedata processing system if a range of the motion is more than a rangethreshold.
 7. The machine-implemented method of claim 1, wherein theadjusting the temperature set point includes selecting the temperatureset point based on the position.
 8. The machine-implemented method ofclaim 1, further comprising determining a state of a peripheral device.9. The machine-implemented method of claim 1, further comprisingdetermining a position of one portion of the data processing systemrelative another portion of the data processing system.
 10. Themachine-implemented method of claim 1, further comprising determining atype of application operating on the data processing system.
 11. Amachine-readable medium storing executable program instructions whichwhen executed by a data processing system causes the system to performoperations, comprising: detecting a motion of a data processing system;determining a position of the data processing system based on thedetecting; and adjusting a temperature set point for the data processingsystem based on the position.
 12. The machine-readable medium of claim11, further comprising instructions that cause the system to performoperations comprising throttling a performance of the data processingsystem to maintain a data processing system temperature below thetemperature set point.
 13. The machine-readable medium of claim 11,wherein the detecting the motion includes measuring accelerationsassociated with the data processing system.
 14. The machine-readablemedium of claim 11, wherein the determining the position includesincreasing a confidence for a first location of the data processingsystem if the motion is not detected within a first time interval; andincreasing the confidence for a second location of the data processingsystem if the motion is detected within the first time interval.
 15. Themachine-readable medium of claim 11, wherein the determining theposition includes increasing a confidence for a first location if a rateof the motion is less than a rate threshold; and increasing theconfidence for a second location of the data processing system if a rateof the motion is more than a rate threshold.
 16. The machine-readablemedium of claim 11, wherein the determining the position includesincreasing a confidence for a first location if a range of the motion isless than a range threshold; and increasing the confidence for a secondlocation of the data processing system if a range of the motion is morethan a range threshold.
 17. The machine-readable medium of claim 11,wherein the adjusting the temperature set point includes selecting thetemperature set point based on the position.
 18. The machine-readablemedium of claim 11, further comprising instructions that cause thesystem to perform operations comprising determining a state of aperipheral device.
 19. The machine-readable medium of claim 11, furthercomprising instructions that cause the system to perform operationscomprising determining a position of one portion of the data processingsystem relative another portion of the data processing system.
 20. Themachine-readable medium of claim 11, further comprising instructionsthat cause the system to perform operations comprising determining atype of application operating on the data processing system.
 21. Asystem, comprising: a memory; and a processor coupled to the memory,wherein the processor is configured to detect a motion of a dataprocessing system; to determine a position of the data processing systembased on the detecting; and to adjust a temperature set point for thedata processing system based on the position.
 22. The system of claim21, wherein the processor is further configured to throttle aperformance of the data processing system to maintain a data processingsystem temperature below the temperature set point.
 23. The system ofclaim 21, wherein the detecting the motion includes measuringaccelerations associated with the data processing system.
 24. The systemof claim 21, wherein the determining the position includes increasing aconfidence for a first location of the data processing system if themotion is not detected within a first time interval; and increasing theconfidence for a second location of the data processing system if themotion is detected within the first time interval.
 25. The system ofclaim 21, wherein the determining the position includes increasing aconfidence for a first location if a rate of the motion is less than arate threshold; and increasing the confidence for a second location ofthe data processing system if a rate of the motion is more than a ratethreshold.
 26. The system of claim 21, wherein the determining theposition includes increasing a confidence for a first location if arange of the motion is less than a range threshold; and increasing theconfidence for a second location of the data processing system if arange of the motion is more than a range threshold.
 27. The system ofclaim 21, wherein the adjusting the temperature set point includesselecting the temperature set point based on the position.
 28. Thesystem of claim 21, wherein the processor is further configured todetermine a state of a peripheral device.
 29. The system of claim 21,wherein the processor is further configured to determine a position ofone portion of the data processing system relative to another portion ofthe data processing system.
 30. The system of claim 21, wherein theprocessor is further configured to determine a type of applicationoperating on the data processing system.